The investigators will isolate organ-specific epithelial and fibroblast cells and lymphocyte cells from phenotypically normal patients with 6 dominantly heritable cancer syndromes. Similar control cultures will be established from normal patients without the inherited mutation(s). Cells cultures will be used to characterize the cytotoxicity and mRNA expression patterns induced by in vitro cell exposure. Biopsy samples obtained from phenotypically normal, medicinally (chemopreventive) treated and nontreated patients and controls will be used to evaluate differentially displayed mRNA patterns. The in vitro and in vivo mRNA expression profiles will be compared to characterize the effects of chemopreventive agents.